120 EVOLUTION AND ITS MODERN CRITICS

workers are tentatively filling up gaps in the direct
historical evidence. Anyone may legitimately criticize
these deductions, great or small, either by pointing- out
evidence apparently discordant with them, or, less help-
fully, by objecting to the inadequate amount of evidence
supporting them. But there is a third form of criticism
that would not be legitimate, and that is the Chesterton
method of ridiculing any conclusion on the ground that,
if it were true, we should be "perpetually stumbling
over" documentary evidence of it.

In that priceless document, the Bayeux Tapestry,
there burst unexpectedly into the continuity of the story
two figures—" unus clericus et /Elfgyva "—who seem
to have nothing to do with what precedes or follows.
Presumably their story was so familiar to the designer's
contemporaries that mere mention of them was con-
sidered sufficient. Later generations have forgotten
them completely, and their portrayal on the tapestry
only serves to remind us that a great many things
were going on in Normandy about the year 1062 of
which the modern historian knows nothing. In the
same way an unexpected fossil such as Archceopteryx
tells us that during the Jurassic period much was hap-
pening in the animal world at which we can do little
more than guess. And may we not imagine some his-
torical crank, whose pet theory was not supported by
the Bayeux Tapestry, pouring scorn upon it on the
ground that, had it any value, we should be tc per-
petually stumbling over" contemporary documents full
of references to JElfgyva and her priest?

The pabeontological evidence for Evolution may be
summed up as follows : —